Step 1 :We are given that the sample mean \(\bar{x} = 37.5\), the hypothesized population mean \(\mu_0 = 40\), the sample standard deviation \(s = 13.4\), and the sample size \(n = 22\).
Step 2 :We are testing the hypotheses \(\mathrm{H}_{0}: \mu=40\) versus \(\mathrm{H}_{1}: \mu<40\).
Step 3 :The test statistic for a t-test can be calculated using the formula: \(t_0 = \frac{\bar{x} - \mu_0}{s / \sqrt{n}}\).
Step 4 :Substituting the given values into the formula, we get \(t_0 = \frac{37.5 - 40}{13.4 / \sqrt{22}}\).
Step 5 :Solving the above expression, we find that the test statistic \(t_0 = -0.875\).
Step 6 :\(\boxed{-0.875}\) is the final answer.